1. Field of the Invention
The present invention relates generally to wireless communication, and more particularly, to an apparatus and method for performing wireless communication using visible light.
2. Description of the Related Art
Recently, there has been an increasing interest in optical wireless technology being complementary to Radio Frequency (RF) technology, due to the depletion of RF frequencies, the possible confusion (crosstalk) between various wireless communication technologies, the increasing demand for communication security, and the advent of the high-speed ubiquitous communication environment based on 4-th Generation (4G) wireless technology.
In particular, Visible Light Communication (VLC), which delivers information using visible rays or visible light, has many advantages, including allowing users to be aware of coverage of information because they can visually identify the place and direction where the light reaches and progresses, as well as being secure, having a broad band, and guaranteeing free use without restrictions. These advantages of VLC ensure reliable security and enable low-power driving. In addition, VLC is applicable even in hospitals and airplanes where the use of RF is restricted, and may also provide additional information services on electric sign boards such as a Light Emitting Diode (LED) display board. Therefore, studies of VLC are underway in many companies and research institutes.
A VLC system may be realized in various ways according to the apparatus to which VLC is applied. Typically, the VLC system may be realized to perform communication between an Access Point (AP) embodied by applying the VLC technology to any in-building lighting device, and a mobile terminal such as a cellular phone. Generally, VLC communication between an AP and a mobile terminal is performed in a cell formed by an AP applied to one lighting device, considering only physical mobility. However, in the case where only physical mobility is considered, a seamless communication service is possible while the mobile terminal is on the move within the cell, but if the mobile terminal leaves the cell, the seamless communication service may not be possible due to the interruption of communication.
Therefore, there is a demand for a method capable of performing VLC considering logical mobility, to allow a mobile terminal to maintain communication even while moving from one cell to another.